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What is cavity wall insulation?

Cavity wall insulation is a system whereby material is injected into the gap (or cavity) between a property’s inner and outer walls to help prevent heat loss. There are many different types of insulation that can be fitted, such as ThermaBead Carbon Saver which is one of the most thermally efficient products on the market. As such, there is a type of insulation suitable for most properties built with cavity walls.


How do I know if I have cavity walls?

Most houses built from 1920 onwards have cavity walls. The easiest way to tell is from the pattern of the bricks on the outside of your house. However, houses built in the last ten years or so are likely to have cavity walls that are already insulated.

If the brickwork has been covered, you can determine if it has a cavity by measuring the external wall at a window or door. If the wall is more than 260mm in depth then it probably has a cavity, anything narrower will suggest that it is a solid wall construction.


What are the benefits of having cavity wall insulation fitted?

Houses built with cavity walls generally have thermal performances which are well below the standards required by current building regulations. This means that insulating the walls could not only significantly reduce heat lost from your home and decrease your annual heating bills by up to £250*, but it can also help you reduce your carbon footprint by as much as 1,040kg* every year.

*Source: Energy Saving Trust website, February 2014. Estimated figures based on insulating a detached, gas-heated home.


How is cavity wall insulation fitted?

Each elevation of the property has small holes carefully drilled out in compliance with BBA specifications. Insulation is then blown via a long hose into each of the property’s elevations. Once all walls have been insulated, the holes are then filled and the site is returned to its previous state.


What types of properties can be insulated?

Cavity wall insulation is suitable for most homes which have a cavity space of at least 40-50mm between bricks, and held together with wall ties. 99% of properties which traditionally could not be insulated because the standard BBA drill pattern could not be followed can now be insulated using ThermaBead’s Thermascopic Bead Lance. The Lance allows for a complete cavity fill by drilling only the end of the wall.


What about a semi-detached property, do the blown beads

go into the next house?

If the other house is not already insulated, the installer will fit a cavity barrier at the party wall line, so that no insulation will work its way through.


Will the technicians need to come into the house?

In order to comply with health and safety regulations, the technicians are required to carry out pre and post installation checks in your home. These checks include assessing whether or not your home has adequate ventilation in place to prevent carbon monoxide poisoning and mould growth. It might also be necessary for the technicians to internally drill some of your walls for access issues, but this will be discussed with you by the surveyor.


Does anything else need to be done prior to installation?

We recommend that any valuables are removed from walls, shelves or windows sills on any external walls prior to installation, as the drilling can cause vibrations. Drilling the walls also unavoidably causes dust. To avoid as much disruption as possible, we recommend that all windows and doors are closed before the installation proceeds, and your neighbours are informed so that they can do the same.

We also suggest that anything outside your home which may be affected by the dust, such as vehicles or clothes on the washing line, are removed from the areas to be insulated. To avoid any delays in your installation, it is also necessary to ensure that there is adequate parking close to your property for a Luton Box van.


How long will the installation take?

An average sized property could take between 2-3 hours.


Is the cavity wall insulation guaranteed?

A 25-year guarantee is supplied for each property. The guarantee is transferable to any subsequent owners of the property.


How long does the insulation last?

Cavity wall insulation should last for the lifetime of the house.


Can any existing insulation be removed?

Existing blown cavity wall insulation can be removed and replaced with superior performing EPS bead.



What is loft insulation?

Loft insulation can be any kind of insulation that is installed in the loft space of a building to help prevent heat loss through the roof. There are four basic types of insulation: matting (also known as blanket or quilt insulation), loose-fill, blown and rigid insulation boards. As such, there is a type of insulation suitable for most properties.


What are the benefits of having loft insulation fitted?

Up to 25% of the heat generated in the average home can be lost through your loft space if it is not properly insulated. By fitting the governmental recommended depth of 270mm of insulation in your loft, you could save up to £250 and around 1,050kg of CO².*

*Source: Energy Saving Trust website, February 2014. Estimated figures based on insulating a detached, gas-heated home.

Does the loft need to be clear for insulation to be fitted?

In order for the technicians to access all areas of your loft, it needs to be no more than 10% full. However, we can clear the loft for you at an additional cost. If you have a boarded area in the loft that you do not wish to remove, it is standard practice to lay the insulation over the boards. This does however mean that you will no longer be able to use your boarded area for storage.


Does anything else need to be done priorto installation?

To make the installation as quick and simple as possible, we advise that customers turn off the heating two hours prior to the insulation being fitted. This is to allow time for the property to cool down, which makes it safer for the technician to work in your loft and fit any hot water tank jackets or pipe insulation that may be required.


How is loft insulation fitted?

If your loft has easy access, regular joists and some existing insulation already, the new insulation material is laid between the joists and then cross laid over the top to achieve the recommended depth. However, if your loft does not have any existing insulation the matting we fit will not be cross laid. Instead, the required thickness of mat will be cut so that it tightly fits the joists beneath, in order to avoid voids or waving. Any pipes and tanks which require insulation are then insulated, along with the loft hatch if necessary.


How long does it take to install?

It takes just a couple of hours for the average property to have loft insulation fitted.


Will fitting loft insulation cause a mess?

Our technicians are trained to make as little mess as possible when installing loft insulation. Dust sheets can be laid down along almost the whole route the workmen will take to access your loft to protect your flooring, although unfortunately they cannot be used to protect your stairs. Any packaging left at the end of the installation will be taken with the crew when they leave.


Will the insulation interfere with the ventilation in the loft?

In order to allow adequate ventilation in your loft, the insulation will be fitted at a suitable distance away from the eaves. If possible, vent wedges are also fitted to aid the circulation of air in the loft.


Will the insulation affect any wiring in the loft?

All high voltage cables will be lifted where possible. If this cannot be achieved, a 75mm channel will be created around them. It is, however, perfectly safe to cover normal household wires.


Can I use my loft for storage after insulation?

Once the loft has been insulated, the joists will not be visible and walking in the loft could be dangerous. As such, we recommend that you do not access your loft without the use of crawl boards and knowledge of the exact position of the joists.